* EU regulators cleared German part of Cemex, Holcim deal early this month (Adds Cemex comments, Holcim and Commission declined to comment)

By Foo Yun Chee

BRUSSELS, July 11 (Reuters) - Europe's antitrust regulator has objected to Cemex's plan to acquire Holcim's Spanish units, a person familiar with the matter said on Friday, denting the Mexican cement producer's hopes of getting EU approval without concessions.

Cemex and Holcim unveiled the deal in August last year, part of which included the Swiss-based peer taking over Cemex's German businesses. The European Commission cleared this deal unconditionally earlier this month.

The Spanish part however triggered an in-depth probe by the EU competition watchdog in April. Its preliminary review showed that the takeover would substantially curb competition in the grey cement market in certain parts of Spain.

"The European Commission has sent a statement of objections to the companies," the person said, referring to a document which backs up the EU watchdog's views that the deal would be a significant impediment to competition.

Reacting to the new, Cemex said: "We cannot comment and the process is following its normal course. Proper disclosure will be made when we have to make it."

The source said Cemex had offered some concessions during the Commission's preliminary review but these were not considered to be sufficient. The Commission has set a Sept. 5 deadline for its decision. (Additional reporting by Gabriela Lopez in Monterrey and Joshua Franklin in Zurich; editing by Robin Emmott)